Acute unilateral obstructive uropathy

Alternative names:

obstructive uropathy - unilateral - acute; ureteral obstruction

Definition:

A disorder involving sudden blockage of urine flow out of the ureter of 1 kidney, resulting in backup of urine and injury to the kidney (see also reflux nephropathy).

Causes, incidence, and risk factors:

Unilateral obstructive uropathy occurs when the kidneys produce urine normally, but the urine is unable to drain out of the affected ureter into the bladder. The urine backs up causing distention of the kidney structures, including the renal pelvis and calyces (hydronephrosis).

Sudden blockage of one ureter causes acute unilateral obstructive uropathy, while slow, progressive blockage causes chronic unilateral obstructive uropathy. The most common cause for acute unilateral obstructive uropathy is a kidney stone, although any condition (such as trauma) that suddenly causes obstruction of a single ureter could cause the disorder. In children, stricture of the ureter (congenital) is a common cause.

Hydronephrosis caused by acute unilateral obstructive uropathy may result in permanent damage to the kidney (failure of one kidney) and may be a cause of hypertension. It usually does not cause symptoms of kidney failure unless there is only one functioning kidney because the function of one kidney is sufficient to sustain life.

Acute unilateral obstructive uropathy occurs in 1 out of 1,000 people.